Digital halftoning is a technique for displaying a picture on a two-dimensional medium, in which small dots and a limited number of colors are used. The picture appears to consist of many colors when viewed from a proper distance. For example, a picture consisting of black and white dots can appear to display various gray levels. Digital printers, which were initially pure black and white machines with a very coarse resolution, have evolved to accommodate colors, finer resolutions, and more recently, more than one bit of information per pixel (referred to as “multi-bit” or “multi-tone”). In multi-bit printers, the output is no longer necessarily binary (e.g., each pixel is either “on” or “off”). However for historical reasons the output continues to be referred to as an “halftone image” or an “multi-bit halftone image. With the prevalence of devices having multi-bit capability there is a potential to improve overall image quality of print jobs using multi-bit halftoning.
Accordingly, an algorithm to perform multi-bit halftoning to create an image screen is desired.